Hydrochloric Acid → 3-[4-(3-Chlorophenyl)-1-ethyl-7-formyl-2-oxo-1,2-dihydro-1,8-naphthyridin-3-yl]propanoic acid

Participants

Reaction Conditions

Reaction Steps

A DMF solution of 3-(3-chlorobenzoyl)-6-dimethoxymethyl-2-ethylaminopyridine was treated with sodium hydride at 0° C. and then monoethyl chloroglutarate was added thereto, followed by heating at 80° C. under stirring. Thereafter, the reaction mixture was worked up in a usual manner. The resulting compound was dissolved in ethanol and sodium methoxide was added thereto at 0° C., followed by heating under reflux for 1 hour. The reaction mixture was cooled to 0° C. and then concentrated sulfuric acid was added thereto, followed by heating under reflux for 1 hour. Thereafter, the reaction mixture was worked up in a usual manner. The resulting compound was dissolved in dioxane and 6M hydrochloric acid was added thereto at 0° C. and, after being warmed to room temperature, the whole was stirred for 3 hours. Thereafter, the reaction mixture was worked up in a usual manner to obtain 3-[4-(3-chlorophenyl)-1-ethyl-7-formyl-2-oxo-1,2-dihydro-1,8-naphthyridin-3-yl]propanoic acid. NMR1: 10.12 (1H, s), 7.70 (1H, d, J=8.1 Hz), 1.44 (3H, t, J=6.9 Hz).

Provenance & Evidence